Fig 1.
Schematic illustration of experiment.
Table 1.
The specifications of the experimental soil samples.
Fig 2.
Experimental materials.
Table 2.
Additions of high–performance ester adhesive materials and water–retaining materials.
Table 3.
Additions to high–performance ester composite materials.
Fig 3.
Experimental equipment and specimens.
Fig 4.
Schematic diagram of 15 FTCs process.
Table 4.
Comparison of lab-based FTCs conditions with real-world data from northern China.
Fig 5.
Changes in properties of HPEMs under different numbers of FTCs.
(Note: Data are expressed as mean ± standard deviation (n = 3)).
Fig 6.
Changes in field water–retention capacity of improved soils under different numbers of FTCs.
(Note: Data are expressed as mean ± standard deviation (n = 3); Groups: A (adhesive), B (water-retaining agent), C (composite).).
Fig 7.
Changes in conductivity of improved soil under different numbers of FTCs.
(Note: Data are expressed as mean ± standard deviation (n = 3); The figure plotted is a stacked plot, with the value of each data being the upper value minus the lower value; Groups: A (adhesive), B (water-retaining agent), C (composite); *p < 0.05 vs. control group).
Fig 8.
Changes in pH of improved soil under different numbers of FTCs.
(Note: Decreased pH values reflect mild acidification toward neutrality; Groups: A (adhesive), B (water-retaining agent), C (composite)).
Fig 9.
Plant growth.
Fig 10.
Changes in plant germination rate under different numbers of FTCs.
(Note: Data are expressed as mean ± standard deviation (n = 3); The figure plotted is a stacked plot, with the value of each data being the upper value minus the lower value.).
Fig 11.
Changes in plant height under different numbers of FTCs.
(Note: Data are expressed as mean ± standard deviation (n = 3)).
Fig 12.
Mechanism related to effect of FTCs on soil improved by HPEMs.
(chematic based on SEM-observed aggregate disintegration and FTIR-confirmed bond cleavage in HPEMs from [21–23,59,60]).